Doctors Opposing Circumcision
Genital Integrity Policy Statement

Chapter Two: The Prepuce

One must understand the nature and function of the
structure that is amputated by circumcision in order to
properly evaluate the effects of male circumcision. This
chapter provides that information.

General Description

The prepuce traditionally has been described as a simple
fold of skin,1 for which
the purpose and function are unknown. This is
inaccurate. In reality, the prepuce is a complex
structure with multiple anatomical and physiological
functions.2

The prepuce is a portion of the entire covering of the
penis. It is specialized tissue, composed of skin,
mucosa, nerves, blood vessels, and muscle
fibers.2 It is anchored by
the abdominal wall at the proximal end of the penis and
at the proximal end of the glans penis. It is not
attached to the shaft of the penis, so, after puberty,
it is free to slide back and forth, everting and
inverting as it does.3 The
sliding/rolling back and forth is called the gliding
action.3,4

A frenulum is found on the ventral side of the penis.
The frenulum serves to tether a movable structure to a
non-movable structure. The penile frenulum returns the
foreskin to its normal protective forward
position.2 Most men report
that the frenulum is highly erogenous tissue.

Peripenic Muscle

In the skin of the penis, there is a sheath of dartos
fascia muscle fibers — the peripenic
muscle.2,3,5 The muscle
fibers keep the prepuce snug against the glans
penis.3 The fibers of the
peripenic muscle sheath form a whorl at the tip of the
prepuce, which act as a sphincter,3 especially in infants and children.
The sphincter also serves to prevent inadvertent
retraction of the prepuce. The peripenic muscle gives
the prepuce great elasticity, allows it to stretch, and
helps to return the prepuce to its forward, protective
position after retraction.2
The elasticity of the prepuce plays an important role in
the erogenous and sexual functions of the prepuce.

Immunology

The prepuce covers and protects the glans penis and
urinary meatus. In most males, the prepuce protects the
sterile urinary tract environment in infancy and
maintains the moistness — beneficial to good
health — of the mucosal surface of the glans penis
throughout life.6 Fleiss
et al. (1998) have identified immunological
functions that help to protect the body from
pathogens:7

sphincter action of the preputial orifice functions
like a one-way valve, allowing urine to flow out but
preventing the entry of infectious contaminants;

apocrine glands of the inner prepuce, which secrete
lysozyme, an enzyme that breaks down cell walls of
pathogens (and also acts against HIV8);

sub-preputial moisture that lubricates and protects
the mucosa of the glans penis; and

high vascularity to bring phagocytes to fight
infection.

The epidermis of the prepuce contains Langerhans cells
that secrete cytokines,2
hormone-like low-molecular-weight proteins, which
regulate the intensity and duration of immune
responses.9 de Witte and
colleagues (2007) report that the Langerhans cells
produce langerin, a substance that provides a
barrier to HIV infection.10

Innervation

The prepuce of the newborn male has extensive
innervation. Winkelmann (1956) reported, “[t]he
principal form of innervation of human newborn prepuce
consists of a deep and superficial network of nerve
fibres in the dermis.”11 Moldwin & Valderrama (1989)
reported an extensive neuronal network in the
prepuce.12

The prepuce of adult males is even more extensively
innervated. Winkelmann (1959) described the prepuce as a
specific erogenous zone with nerves arranged near
the surface in rete ridges.13 Taylor et al. (1996) also
found nerves near the surface in rete ridges and further
described a concentration of nerve endings in a ring of
ridged tissue just inside the tip of the prepuce near
the mucocutaneous boundary, which he named the ridged
band.14 The nerve
endings in the ridged band are Meissner's corpuscles and
Krause's end-bulbs.

The nerves of the penis, including the preputial nerves,
supply sensory input to both the somatosensory and
autonomic nervous systems by different
routes.2 The sensory input
to the somatosensory nervous system is supplied through
the dorsal nerve of the penis, and the autonomic nervous
system is supplied through the parasympathetic nerves,
which run adjacent to and through the wall of the
membranous urethra.

The prepuce is provided with an extensive vascular
network to bring oxygen to support the heavy
innervation.2,7,14

Several writers have commented on the sensitivity of the
prepuce. Winkelmann (1956) wrote, “…it is a
region of great sensitivity and possessed of an abundant
nerve supply,”11 and
later (1959) identified the prepuce as a specific
erogenous zone.13
Falliers (1970) noted the “sensory pleasure
associated with tactile stimulation of the
foreskin.”15 A
landmark study by Sorrells et al. (2007) of the
fine-touch sensitivity of the penis finds that the areas
most sensitive to fine touch are on the
foreskin.16 Circumcision,
therefore, amputates the most sensitive areas of the
penis.

Sexual Function

The prepuce is primary, erogenous tissue necessary for
normal sexual function.2 In
adult life, the gliding action facilitates
introitus4 and reduces
friction and chafing during coitus.5 The movement and stretching of the
prepuce during coitus stimulate the nerve endings in the
prepuce, produce erogenous sensation, and eventually
ejaculation.18,19 The
presence of the prepuce tends to protect the corona of
the glans penis from direct stimulation, helps to
prevent premature ejaculation20,21 and contributes to female
satisfaction.22 (See
Chapter Six for a discussion of the
sexual harm of prepuce excision.)

Natural Development

The great majority of newborn infant boys are born with
the inner surface of the prepuce fused with the
glans.2 In addition, the
tip of the prepuce at birth usually is too narrow to
allow retraction. The duration of these conditions vary
with the individual but can last until the completion of
puberty or longer. For these two reasons, the
non-retractile foreskin is normal in childhood and
adolescence and cannot be considered a disease requiring
treatment.

The first data on development of the retractile prepuce
was provided in 1949 by British pediatrician Douglas
Gairdner.22 Gairdner said
80 percent of boys have a retractable foreskin by the
age of two years, and 90 percent of boys have a
retractable prepuce by the age three. His erroneous
information23 has been
incorporated into medical textbooks and medical school
curricula for decades, and it still is repeated in
medical literature today.24

Gairdner’s data are inaccurate23-25 and, unfortunately, most
healthcare providers have been taught this inaccurate
information,24,25 which
contributes to improper diagnosis of “pathological
phimosis” in the healthy, normal, non-retractile
foreskin. Retractability usually occurs much later than
previously believed.2,24,25
About 44 percent of boys have a fully retractable
prepuce by age 10-112,27,28,29 and about 95 percent have a
fully retractable prepuce by age 18.2,27 Non-retractile foreskin is the more
common condition until 10-11 years of age. Thorvaldsen
& Meyhoff (2005) report that the mean age of first
foreskin retraction is 10.4 years.29 Non-retractile foreskin in childhood
and adolescence is not a disease and does not require
treatment.

Ballooning of the prepuce in childhood during urination
is harmless and self-limiting. Babu et al. (2004)
have shown that ballooning does not cause
obstructed voiding.30
Ballooning disappears with increasing maturity. No
treatment is required.31